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14 DESIGN007 MAGAZINE I DECEMBER 2020 had something to work on, and almost never was that something right. I did a brief piece on this, which wasn't even a re- spin; it had to do with how much money we spent to accelerate getting the pro- totype of a PCB. In the case I was working on there, the difference between a three- day turn and a 10-day turn was only about $5,000, and they wouldn't spend it. One evening, we were doing the budget for the next quarter, and it came out to a little bit less than $2 million a week to run the project. I told manage- ment, "If I spend $5,000 and take a week out of this budget, doesn't that make good sense for our return on invest- ment?" Finally, someone had quantified the cost of time for them because no one had done that. And that's not even a respin; that's just being smart about where you spend premiums. Now, that gives you a yardstick for how much a respin costs. If you're lucky, and a respin only takes six weeks and $2 million, isn't it worth spend- ing another week getting it right? I think so. Barry Matties: What does it take to get it right to begin with? What's the recipe? Ritchey: Analysis. In the case of the micropro- cessor, they built an emulator and ran the soft- ware on the emulator to make sure that the two worked together correctly before cutting the two of them. In the case of the box at 3Com, it was a question of taking long enough to make sure you had all the design rules right and that the netlist is correct. Another example, which is more painful because it made a company disappear, was at Maxtor. At the time, there were eight companies in the disk drive busi- ness, all trying to make the same thing. When I took over engi- neering at Maxtor, they had built into their budget six spins of the prototype. I asked them why they had done six spins. They would hand over a sche- matic to the layout people, and all the resistors were TBD. "When are you going to find out?" "After we get the board, we'll figure that out." That was a massive operation. That was how they operated. They were up against Western Digi- tal and Seagate, and both of those companies were doing analytical work, and the rest is history. There is no Maxtor. Matties: Why would a company allow so many respins? Is doing it right the first time that chal- lenging? Ritchey: No, but their managers are not engi- neers. Matties: But even aside from engineers, if you just take the economics, you don't have to be an engineer to do the math. Ritchey: If you look at those companies, they are run by people with MBAs and degrees in finance, not engineering. That's what undoes them. Matties: They should be able to look at it and see that a respin is going to cost them millions of dollars. It seems that their math sensibilities would kick in. Ritchey: You would think so, but that's not how it works. Bob Noyce said this more than once when Silicon Valley was having a lot of failures. There was a forum we used to have once a month in the evening to discuss prob- lems with businesses in the valley. Lee Ritchey

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